Prioritize closer results even if only partially matching

Description

However, most of the time, the user doesn't know or use the official full name of a place. However, if he browses near it, we shouldn't give him results about places on the other side of Earth.

If we still want to give the user the choice to prioritize exact matches, a link could be used to switch back to the old behavior. That link could be named like "View exact matches for your search". Those would still be ordered by distance, but would prioritize exact matches.

Google Maps actually works like this, trying to show the more useful results first (typically, near where the user is).

Note: I added "SHS" in alt_name to make the link work. Before that, "SHS" gave the same kind of results.
We should not expect contributors to guess and specify in alt_name the exact name (if there is one) that most users are going to search for.